A variety of laser treatments have Federal Drug Administration (FDA) approval for a wide range of dermatological conditions ranging from scar tissue removal, reduction of birthmarks and other pigment related problems including lentiginous conditions such as freckles, liver spots and sun damaged skin, to wrinkle reduction and skin tightening. Although each approved treatment may use a different laser, each of which may have a different wavelength and power, there are some commonalities among the array of lasers currently used in these dermatological treatments.
The most important may be that they all have pulse-widths in the nanosecond range. Although the individual pulse powers are relatively low—typically about 200 mJ per pulse—the long pulse-widths allow time for the heat produced to diffuse out. This diffusion not only means that more total energy has to be delivered in the form of a greater number of pulses—lengthening the time for a typical procedure to 1 to 2 hours—but also that the surrounding tissue may be heated significantly—typically to the extent of a second-degree burn. This has, in the past, made laser procedures painful at the time, and required recovery times of 1 to 2 weeks. The industry has attempted to address the pain factor by developing a range of topical anesthetics to be applied during the procedures. They have also developed ways of cooling the surrounding tissue using a variety of methods from cool air jets, water spray to having piezoelectric cooling heads as part of the laser delivery head.
These advances have mitigated the pain and recovery problems significantly, though not completely. The cooling systems may be difficult to apply, and the powerful topical anesthetics pose risks in of themselves.
What is needed is a system that can deliver the benefits of laser dermatological procedures without the side-effects, particularly the heating or damage to the surrounding tissue, and in much reduced treatment times.